The binding sites of Calcium atom in the structure of Crystal Structure of Human Coagulation Factor Xa Complexed With RPR209685 (pdb code 1nfw). This binding sites where shown with 5.0 Angstroms radius around Calcium atom. The 1nfw structure was solved by S.MAIGNAN, J.P.GUILLOTEAU, with X-Ray Crystallography technique, brief refinement statistics is given in the table below: